How to plant pot-grown bearded irises

How to plant pot-grown bearded irises

Bearded irises thrive in hot, sunny conditions. Find out how to plant them for the best results, in our guide.

A table displaying which months are best to sow, plant and harvest.
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
At its best
At its best

Plant is not at its best in January

Plant is not at its best in February

Plant is not at its best in March

Plant is not at its best in April

Plant is at its best in May

Plant is at its best in June

Plant is not at its best in July

Plant is not at its best in August

Plant is not at its best in September

Plant is not at its best in October

Plant is not at its best in November

Plant is not at its best in December

To do
To do

Do not To do in January

Do not To do in February

Do not To do in March

Do not To do in April

Do not To do in May

Do To do in June

Do To do in July

Do To do in August

Do To do in September

Do To do in October

Do not To do in November

Do not To do in December

Finding plants to grow in a hot, dry border can sometimes be tricky. Bearded irises will thrive in these conditions, and require very little care or watering once their roots are firmly established.

Bearded irises only flower well if their rhizomes get baked in full sun, while their grey-green leaves reflect the heat, helping to reduce water loss. The flowers come in a range of bright and exotic colours, and they bloom from mid-May to mid-June.

The best time to plant bearded irises is from June to October, for flowers the following year. Immediately after flowering is the best time to lift and divide existing clumps. Irises come in three main sizes: dwarf varieties, which are about 15cm tall; intermediates, which reach 60cm in height; and tall varieties, which grow up to 1.2m. With such a wealth of options, you can usually find a variety to fill any gap in a sunny border.

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You Will Need

  • pot-grown bearded irises
  • Trowel
  • Watering can

Total time:

Step 1

Choose potted irises carrying several clusters of healthy leaves. Lift out of their pots and look for healthy roots.

How to plant pot-grown bearded irises - checking the roots
How to plant pot-grown bearded irises – checking the roots

Step 2

Dig a planting hole that is just deep enough to take the rootball. Choose a sunny site with a well-drained soil. You can improve drainage in your soil by digging in plenty of grit before planting.

How to plant pot-grown bearded irises - digging a planting hole
How to plant pot-grown bearded irises – digging a planting hole

Step 3

Settle the rootball into the hole so it’s level with the surrounding soil. Backfill with soil, then firm around the plant. Achieve the best effect by positioning plants in bold groups, with multiples of the same variety growing together.

How to plant pot-grown bearded irises - backfilling with soil
How to plant pot-grown bearded irises – backfilling with soil

Step 4

Ensure the rhizome is on the surface of the soil and not covered with soil, so it’s exposed to the sun. Trim neighbouring plants, if necessary, so they don’t cast shade over your irises.

How to plant pot-grown bearded irises - rhizome on the surface
How to plant pot-grown bearded irises – rhizome on the surface

Step 5

Water the whole area thoroughly, to settle the soil and remove air pockets. Only water again if the soil is very dry. Feed early in the season with a low-nitrogen fertiliser such as bone meal.

How to plant pot-grown bearded irises - watering the iris
How to plant pot-grown bearded irises – watering the iris

Step 6

Mulch the soil with gravel, to retain moisture, but don’t cover the rhizomes. Deadhead irises after flowering by cutting stems back to the fan of leaves. Plants will bloom again next spring.

How to plant pot-grown bearded irises - bearded iris flower
How to plant pot-grown bearded irises – bearded iris flower
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Weed regularly by hand, to stop them taking hold. It’s impossible to hoe round iris without damaging the rhizomes, so don’t try.

Seedlings. Photo: Getty Images.